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WIRELESS SECURITY USING
WPA2

BY :
TUSHAR ANAND KUMAR
ECE-D, REGD. NO.:
1151016015
CONTENTS
 Types of security in WLAN
 Comparison of WEP,WPA,WPA2
 Evolution of wireless security standards
 WPA 2 authentication ,encryption & decryption
 Benefits & vulnerabilities
 Solutions & conclusion
TYPES OF SECURITY IN WLAN
 OPEN : No security configured X
 WEP : Wired Equivalent privacy X
 WPA: Wi-Fi Protected Access
 WPA2: Advance Wi-Fi Protected Access
WIRELESS SECURITY STANDARDS
WPA2 OVERVIEW
 Wi-Fi Protected Access 2


Security standard developed by the Wi-Fi Alliance and is an
implementation of IEEEs 802.11i



Uses Advance Encryption Standard (AES) protocol

 AES in Counter-Mode for encryption
 AES in Cipher Block Chaining-Message Authentication Code (CBC-MAC)
for integrity checking
WI-FI PROTECTED ACCESS 2

Table: two types of WPA2
COMPARING WEP, WPA ,and WPA 2
AUTHENTICATION

Two types of authentication

 Personal mode
 Enterprise mode
PERSONAL MODE AUTHENTICATION


Authentication performed between
client and access point



PSK(Pre Shared Key) &
SSID(Service Set Identification) is
used



AP generates 256 bit from plain text
pass phrase



PMK(Pairwise Master Key) is
generated after authentication
ENTERPRISE MODE AUTHENTICATION



Based on IEEE 802.1x standard
Authentication performed between
:-

1. Client
2. Access Point
3. Authentication Server
 After authentication MK(Master
Key)

Is generated
WPA 2 KEY GENERATION
 4 way handshake initiated by AP
 Confirms clients knowledge of
PMK in personal mode & MK in
enterprise mode

 Pairwise Transient Key created
at clients

 Fresh PTK is derived at AP
1. Key confirmation key
2. Key encryption key
3. Temporal key
WPA 2 KEY GENERATION
 Install encryption and integrity
key

 Control port are unblocked
WPA2 ENCRYPTION
 Two Process happens
1. Data encryption
2. Data integrity

 AES is used in encryption & authentication is a block symmetric cipher
 CCM is new mode of operation for block cipher
 Two underlying modes of CCM
 Counter mode(CTR) achieves data encryption
 Cipher block chaining message authentication code(CBCMAC) to provide data
integrity
MESSAGE INTEGRITY CODE(MIC)
 IV(Initialization Vector) encrypted
with AES & TK to produce 128
bit result

 128 bit result is XOR with next
128 bits of data

 Result of XOR is continued until
all IV are exhausted

 At end,first 64 bits are used to
produce MIC
Figure :AES CBC-MAC
WPA2 ENCRYPTION
 Counter mode algorithm encrypts
the data with MIC

 Initialize counter for first time or
increment counter.

 First 128 bits are encrypted using
AES & TK to produce 128 bits.

 XOR is performed on result and first
message block to give an first
encrypted block.

 Repeat until all 128 bit of blocks has
been encrypted.
Figure: AES counter mode
WPA2 DECRYPTION
 It works in reverse using same algorithm for encryption the counter
value is derived.

 By using the counter mode algorithm and TK , the

MIC and decrypted

data are found out.

 The data is processed by CBC-MAC to recalculate MIC
 If MIC does not match then packet is dropped otherwise data is sent
to network stack and to client
BENEFITS OF WPA2
 Provides solid wireless security model(RSN)
 Encryption accomplished by a block cipher
 Block cipher used is Advanced Encryption Standard (AES)
 IEEE 802.11i authentication and key management is accomplished by
IEEE 802.1x standard

 Key-caching
 Pre-authentication
WPA2 VULNERABILITIES

 Cant stand in front of the physical layer attacks:
RF jamming
Data flooding
Access points failure

 Vulnerable to the Mac addresses spoofing
PROCEDURES TO IMPROVE WIRELESS
SECURITY
 Use wireless intrusion prevention system (WIPS)
 Enable WPA-PSK
 Use a good passphrase
 Use WPA2 where possible
 Change your SSID every so often
 Wireless network users should use or upgrade their network to the
latest security standard released
FUTURE SCOPE
 A new standard IEEE 802.1W task group(TG) approved in
March,2005
 Main Goals
Improve security by protecting the management frames and also being able to
identify
Spoofed management frames normally used to launch DoS attack
THANK YOU!
REFRENCES
 Benefits and Vulnerabilities of Wi-Fi Protected Access 2 (WPA2)
Paul

By

Arana

 The Evolution of 802.11 Wireless Security INF 795 - Kevin Benton
 Wireless LAN Security Issues and Solutions by Pan Feng at 2012
IEEE Symposium on Robotics and Applications(ISRA)

 Security Improvements of

IEEE 802.11i 4-way Handshake Scheme
by Xiaodong Zha and Maode Ma 息2010 IEEE

More Related Content

Wireless security using wpa2

  • 1. WIRELESS SECURITY USING WPA2 BY : TUSHAR ANAND KUMAR ECE-D, REGD. NO.: 1151016015
  • 2. CONTENTS Types of security in WLAN Comparison of WEP,WPA,WPA2 Evolution of wireless security standards WPA 2 authentication ,encryption & decryption Benefits & vulnerabilities Solutions & conclusion
  • 3. TYPES OF SECURITY IN WLAN OPEN : No security configured X WEP : Wired Equivalent privacy X WPA: Wi-Fi Protected Access WPA2: Advance Wi-Fi Protected Access
  • 5. WPA2 OVERVIEW Wi-Fi Protected Access 2 Security standard developed by the Wi-Fi Alliance and is an implementation of IEEEs 802.11i Uses Advance Encryption Standard (AES) protocol AES in Counter-Mode for encryption AES in Cipher Block Chaining-Message Authentication Code (CBC-MAC) for integrity checking
  • 6. WI-FI PROTECTED ACCESS 2 Table: two types of WPA2
  • 7. COMPARING WEP, WPA ,and WPA 2
  • 8. AUTHENTICATION Two types of authentication Personal mode Enterprise mode
  • 9. PERSONAL MODE AUTHENTICATION Authentication performed between client and access point PSK(Pre Shared Key) & SSID(Service Set Identification) is used AP generates 256 bit from plain text pass phrase PMK(Pairwise Master Key) is generated after authentication
  • 10. ENTERPRISE MODE AUTHENTICATION Based on IEEE 802.1x standard Authentication performed between :- 1. Client 2. Access Point 3. Authentication Server After authentication MK(Master Key) Is generated
  • 11. WPA 2 KEY GENERATION 4 way handshake initiated by AP Confirms clients knowledge of PMK in personal mode & MK in enterprise mode Pairwise Transient Key created at clients Fresh PTK is derived at AP 1. Key confirmation key 2. Key encryption key 3. Temporal key
  • 12. WPA 2 KEY GENERATION Install encryption and integrity key Control port are unblocked
  • 13. WPA2 ENCRYPTION Two Process happens 1. Data encryption 2. Data integrity AES is used in encryption & authentication is a block symmetric cipher CCM is new mode of operation for block cipher Two underlying modes of CCM Counter mode(CTR) achieves data encryption Cipher block chaining message authentication code(CBCMAC) to provide data integrity
  • 14. MESSAGE INTEGRITY CODE(MIC) IV(Initialization Vector) encrypted with AES & TK to produce 128 bit result 128 bit result is XOR with next 128 bits of data Result of XOR is continued until all IV are exhausted At end,first 64 bits are used to produce MIC Figure :AES CBC-MAC
  • 15. WPA2 ENCRYPTION Counter mode algorithm encrypts the data with MIC Initialize counter for first time or increment counter. First 128 bits are encrypted using AES & TK to produce 128 bits. XOR is performed on result and first message block to give an first encrypted block. Repeat until all 128 bit of blocks has been encrypted. Figure: AES counter mode
  • 16. WPA2 DECRYPTION It works in reverse using same algorithm for encryption the counter value is derived. By using the counter mode algorithm and TK , the MIC and decrypted data are found out. The data is processed by CBC-MAC to recalculate MIC If MIC does not match then packet is dropped otherwise data is sent to network stack and to client
  • 17. BENEFITS OF WPA2 Provides solid wireless security model(RSN) Encryption accomplished by a block cipher Block cipher used is Advanced Encryption Standard (AES) IEEE 802.11i authentication and key management is accomplished by IEEE 802.1x standard Key-caching Pre-authentication
  • 18. WPA2 VULNERABILITIES Cant stand in front of the physical layer attacks: RF jamming Data flooding Access points failure Vulnerable to the Mac addresses spoofing
  • 19. PROCEDURES TO IMPROVE WIRELESS SECURITY Use wireless intrusion prevention system (WIPS) Enable WPA-PSK Use a good passphrase Use WPA2 where possible Change your SSID every so often Wireless network users should use or upgrade their network to the latest security standard released
  • 20. FUTURE SCOPE A new standard IEEE 802.1W task group(TG) approved in March,2005 Main Goals Improve security by protecting the management frames and also being able to identify Spoofed management frames normally used to launch DoS attack
  • 22. REFRENCES Benefits and Vulnerabilities of Wi-Fi Protected Access 2 (WPA2) Paul By Arana The Evolution of 802.11 Wireless Security INF 795 - Kevin Benton Wireless LAN Security Issues and Solutions by Pan Feng at 2012 IEEE Symposium on Robotics and Applications(ISRA) Security Improvements of IEEE 802.11i 4-way Handshake Scheme by Xiaodong Zha and Maode Ma 息2010 IEEE